The radio spectrum resources in most countries around the world are statically partitioned into blocks allocated for different purposes. The characteristics of spectrum usage, such as type of service (e.g., cellular, public safety, television broadcast), maximum transmit power, and the like are a-priori specified, and are time and location invariant. Disadvantageously, such current spectrum allocation rules were based on antiquated technology assumptions, as well as in the absence of adequate market mechanisms. Furthermore, existing spectrum management processes, involving primary user licensing or property rights on one extreme and complete unlicensed usage, or commons, on the opposite extreme, have numerous serious drawbacks resulting in disadvantageous associated business and operational implications.
The business implications of such existing spectrum management processes has led to purpose-built networks involving capital-intensive steps of acquiring licensed spectrum, deploying network infrastructure, and offering and operating end-user services over the network infrastructure using the licensed spectrum. Furthermore, the process of acquiring licensed spectrum tends to be a slow, expensive process, especially due to the “big player syndrome” in which only very large service providers can compete. Disadvantageously, such business implications result in slow innovation of both networks and services (e.g., as evident in the inordinate delays in the introduction of Third Generation (3G) wireless networks).
The operational implications of such existing spectrum management processes include: (1) although a majority of spectrum is licensed for use, a large portion of the licensed spectrum is highly underutilized (e.g., public safety spectrum, military and government spectrum, and certain ultra high frequency (UHF) television spectrum) and (2) several licensed spectrum bands (e.g., cellular and personal communications services (PCS) bands) are utilized, however, utilization varies dramatically over space and time. By contrast, unlicensed spectrum bands have experienced unfettered network deployment due to low cost technology. In other words, spectrum is access limited rather than throughput limited.